Dwyer 3000-0AV Photohelic Pressure Switch / Gage

Dwyer Instruments, 3000-0AV, Photohelic Pressure Switch / Gage, 0-.50 / 500-2800 F.P.M.

Features:

• 3-in-1 instrument allows the reduction of several instruments with one product, saving inventory, installation time and money
• Patented design and 1% full scale dead band provides quick response to pressure changes means no delay in switching and chatter-free operation
• A wide range of models that can meet pressure measurement specifications from low to very high
• Bezel and front cover (with set point knobs and zero adjustment screw) removed to expose Photohelic gage set point mechanism. Cover is clear polycarbonate plastic.
• Gage pointer and light shutter are mounted on helix and balancing counterweight. Shutter passes through slot in optical limit switch to expose photo-transistors to integral infrared light source or mask them depending on applied pressure.
• Light shield effectively protects photo-transistors from strong outside light sources yet allows free pointer movement. It also gives interior a clean "finished" look.
• Optical limit switches are used for reliability and long service life. Attached directly to set pointers, they are individually aligned to assure precise switching accuracy.
• Semi-Flexible drive shaft connects to set point knobs.
• Plastic enclosure protects electronic components and electrical connections.
• Polycarbonate connection or terminal board is self-extinguishing.
• Glass-epoxy printed circuit boards for durability and performance.
• Load relays are DPDT with latching feature for maximum application versatility.
• Electronics are designed to operate on 50/60 Hz, 120 volt current with 10% over or under voltage.
• Switch set pointers show switch settings at all times.
• Spring loaded friction clutch prevents operator damage of set point mechanism.
• Zero adjustment screw connects to screw in cover to adjust zero pressure reading.

Applications:

• Air conditioning systems
• Clean rooms
• Fume exhaust systems

3-in-1 Indicating Gage, Lo-Limit and Hi-Limit Control. The Photohelic Switch / Gage function as versatile, highly repeatable pressure switches combined with a precise pressure gage employing the time-proven Magnehelic gage design. The Photohelic switch / gage measures and controls positive, negative or differential pressures of air and compatible gases. Two phototransistor actuated, DPDT relays are included for low / high limit control. Easy to adjust set point indicators are controlled by knobs located on the gage face. Individual set point deadband is one pointer width - less than 1% of full scale. Set points can be interlocked to provide variable deadband - ideal for control of fans, dampers, etc. Gage reading is continuous and unaffected by switch operation, even during loss of electrical power. Choose from full scale pressure ranges from a low 0-.25 in (0-6 mm) w.c. up to 30 psi (21 bar); single positive pressure to 6000 psig (413 bar).